KANSAS CITY, Mo. — One of these days, the Red Sox believe Drew Pomeranz is going to remember how to piece together all the moving parts to his complicated delivery.

Tomorrow at McCoy Stadium is when the club hopes Pomeranz can start his 2018 season the right way.

“The most important thing for him — I don’t feel he rushed himself in the last one but I don’t think he was really where he wanted to be, just felt like he was going to be able to contribute the way he was because he was healthy, and at this level if you’re not right, they’ll take advantage of it,” said manager Alex Cora about Pomeranz’ rehab start with Pawtucket earlier this week when the left-hander allowed four home runs.

“He wasn’t as sharp as we wanted him to (be),” Cora said, “we were running him out there, we felt like every outing he was going to get better and he did for a little bit but this time he wants to make sure his mechanics are where they’re supposed to be. He looked a lot better in that simulated game, body-wise, and his arm so hopefully he can get there and contribute.”

“He said he was off mechanics-wise,” said Cora. “He felt fine afterward, he faced some good competition, honestly — look at that lineup — but it was more about mechanics, timing off, his arm wasn’t getting where he wanted as far as breaking ball and fastball. He got his repetitions, not as many as he wanted to, but it was a good start to his process.”

Pomeranz’ mechanics are different than many other starters.

There’s more movement, which means that when there’s a problem it’s tougher to find and to fix.

“It’s not simple compared to David (Price) or Chris (Sale), that is kind of like ‘up and go,’ ” said Cora.

“With him, there’s a lot of moving parts, he needs to get to that back leg and then at the end he has to go up and come over.

“Just watching him last year and watching him this year, I know what he’s talking about now. His timing is off. Also talking to (Pawtucket pitching coach Kevin Walker) down there, he felt he was way off, as far as his mechanics.

“We have to make sure he’s sharp, that is what’s going to help him gain his velocity if he’s healthy and he feels he’s healthy. Hopefully if he can get his mechanics right, he can gain two or three miles per hour and go from there.”

Just because it’s complicated with Pomeranz doesn’t mean the Red Sox want him to change to a simpler delivery.

“That’s who he is and that’s what makes him tough, too,” said Cora. “It’s tough to pick up the ball with his delivery.”